Safety paper



Patented June 24, 1941 Ohio; said Yackly assignor to said Sherman; Katherine M. Sherman, William C.v Sherman,

and Wellmore B. Turne Sherman, deceased l No Drawing. Application January SerialNo. 119,5241":

r, executors of John wai t; (01.

This invention pertains to) papermanu facture and comprises a safety papersuitable for checks; vouchers, money orders,- valuablerecords, agree ments and legal papers whlchitisdesired-to protect against change and more particularly to a paper which is adapted to'lvisu'ally indicate any attempt to tamper therewith' and efforts to change or add to a written record; 1

Safety, paper-is now commonly' employed whereon attempted erasures 'be'come plainly visible but do not deter. attempts of a skilled penman to change the written record by adding-'toor'reforming existing letters or 'words to raise the amount of a check 'or voucher or change a'signa' ture or the import'of written matterwithout ne cesslty of making" erasures.

The present paper has the conventional'surfa'ce and appearance of ordinary writing or'printing paper and bears no visible'indication'which' will iorewarn' a 'iorger or others of its peculiar character.' However, the paper is so'treatedfeith'er during- "manufacture or by surface application thereafter, that when written upon with ordinary commercial'inks 'such as are generally-available, the inli lines will spread or feather out asupon blotting paper. However; the paper is'susc'eptible of being writtenupon in the ordinary manne with specially prepared ink which produces thereon a written record having the natural and normal appearance made by conventional inks.

lhe purpose of the invention is to provide a protective paper which will readily indicate any attempt to change the record thereon or add thereto, even though no erasure be made,'and thereby'serve as a deterrent to dishonesty.

an important object of the invention is to provide a safety paper which may be economically manufactured and which will possess a normal conventional appearance, the special character of which is concealed.

a further object of the invention is to provide a protective paper which will be incapable of receiving legible records when written in ordinary commercial ink such as are generally available, but which will legibly receive written records when made with a specially prepared ink.

A further object of the invention is to provide a suitable ink for use upon the specially prepared The safety. paper "herein described; is produced by treating ordinary paper with. conditioning mixture: of aipigment such astitanlumoxide, an alcohol such as glycerol; water-and a silicate of which sodiumsilicate'is a suitable material. -With no intentzto unduly limit the scope or application of the'invention, but merely for illustrative purpose', the following formulaof ingredients an'd proportions thereof has been found quite effective: r

Per-cent- Titanium dioxide 14.15 Glycerol 4.69 Water 35.46 Sodium silicat e L; 45.75

In preparingthe mixture the pigment is ground in the water and alcohol and the silicate is subsequently added and the grinding operation continued until the pigment is thoroughly dispersed throughout the media. If the paperis .to.be tinted, a dye material such as crocein scarlet con centrate is added to the mixture in sufficlent quantity to impart thedesired shade ofcolor.

The-mediathus'prepared' 'ma'y' be incorporated in the paper pulp material-during its manufacture or it may be applied to the paper while being formed onthe Fourdrinier machine or as it leaves suchapparatus. Preformed paper maybe treated by dipping it in thetreatment-medla or by brushing it onto' the surface of the paper. In some instances it maybe desirable to treat only isolated areas of the paper stock upon which writteninserts are to be made, in which case the material is necessarily applied to previously manufactured paper, preferably by an imprinting op eration whereby the media may be applied only throughout well defined spaced areas.

Upon application of ordinaryicommercial writing inks to the treated paper the ink lines will spread or feather out into a fuzzy blur similar to its action on blotting paper. It is found that some inks in general use .will fade and lose their colors quite rapidly when applied to such treated surface. It is quite impossible to write legibly upon such specially treated paperwith ordinary inks. The treated paper being of ordinary appearance does not indicate in advance its peculiar nature and hence affords no forewarning.

In order to prbduce legible records on the treated paper a special writing fluid is employed consisting of a fast dye of which Victoria blue base concentrate is an example, combined with a pigment such as iron blue, an alcohol of which ethyl alcohol is preferred and a gum of which a synthetic gum of polyvinal acetate type is deemed suitable.

A typical formula stated for illustrative purpose, but not as a limitation comprises:

Per cent Dye or pi ment. 7,52 Alcnhnl a 30.07 Gum 62.41

In preparing this writing fluid the gum and pigment are ground in the alcohol until thoroughly dispersed and of uniform character. This writing fluid does not run or feather out as does ordinary commercial inkwhen applied to the treated paper surface but produces a clear legible line which is of fast color which takes on a permament darker hue when subjected to light.

Inasmuch as safety paper is extensively used for printing purposes, in the production of checks, vouchers and the like, it has been found desirable to produce a complementary printing ink for use thereon.

Such printing ink comprises afast type such as victoria blue'base concentrate, or a pigment of whichiron blue is an example, combined with a lithographic varnish, a drier material such as cobalt or manganese oxide and a suitable waxrof which bees wax is found satisfactory and a oil.

v Typical formulae submitted for illustrative purposes comprise:

plate The herein described treatment of the paper renders itmore absorptive than ordinary papers or increases the capillary attraction eflect thereof whereby ordinary writing fluid which is slow drying will be rapidly absorbed and will be drawn by the increased capillary attraction into a more widely spread area. The prescribed ink for writing on such prepared paper having a gum base is more viscous and more rapid drying and hence resists the capillary attraction and does not spread or leather out as does ordinary ink.

In the formula which is here stated merely for illustrative purpose, it being understood that other materials of analogous character may be substituted therefor, the titanium affords the absorbent characteristic while the sodium silicate -is used as a binder, and the glycerol as a plasoperation of the character described possessing the particular features of advantage before enumerated as desirable, but which obviously is susticiser to prevent excessive hardening and make the coating pliable. The water is merely the ve hicle to render the mixture sufliciently fluid for application. The alcohol which renders the inkinitially more fluid rapidly evaporates after application to the paper leaving the remaining ceptible of modification in its form, proportions, detail construction and arrangement of parts without departing from the principle involvedor sacrificing any of its advantages. v

While inorder to comply with the statute, the invention has been described in language more or less specific as to structural features, it is to be understood that the invention, is not limited to the specific features'shown, but that the means and construction herein disclosed comprise the .fore, claimed many of its forms or modifications within the legitimate and valid scope of the appended claims.

Having thus described our invention, we claim:

-1. A protective record including the' combination of a record material simulating the appearanceof ordinary record material to be'written upon, and having a porous, absorptive surface, and a non-penetrating ink for use therewith sufficiently viscous to resist capillary attraction of the absorbent record material and produce lines and characters in simulation of those produced by ordinary ink on ordinary writing material.

2. The herein described method of making records which includes treating a writing material to increase the normal capillarity thereof while maintaining the normal appearance of the writing material, and writing on the material with an ink suiflciently volatile to resist the effect of the increased capillarity otthe writing material and produce sharply defined. lines and characters in simulation of characters producible with ordinary ink on the writingmaterial prior to such treatment thereof.-

3. A protective record including a writing material simulating ordinary writing material in appearance and having a degree of capillarity in excess of that or ordinary writing material, and an inscription thereon in a complementary ink resistant to the excess capillarity oi the writing material and which produces sharply defined lines and characters when applied thereto in simulation of those produced on ordinary writing material by ordinary ink. g

4. In a protective record, the combination with a record material simulating ordinary writing material in appearance and having a degree of capillarity in excess of that of ordinary record material and such as to effect rapid spreading of ordinary ink, of a complementary ink sufficiently non-flowing upon exposure to air as to resist the capillarity of the record material and produce sharply defined lines and characters when applied thereto in simulation of those produced on ordinary writing material by ordinary ink.

5. A writing material treated with an absorb ent, a plasticizer and abinder material to increase the capillarity thereof over and above the normal capillarity of ordinary writing material while simulating the appearance of ordinary writing material, whereby the writing material is rendered incapable of receiving legible inscriptions written in other than writing fluid sufilclently non-flowing upon application to the treated material as to resist the increased capillarity of the treated writing material and produce lines and characters in simulation of those produced by ordinary ink on ordinary writing material.

8. A writing material treated with a mixture oi titanium dioxide, glycerol and sodium silicate to increase the capillarity thereof over and above that of ordinary writing material, whereby the writing material is rendered incapable oi receiving legible inscriptions written in other than writing fluid sunlciently non-flowing upon application to the writing material as to resist the increased capillarity of the treated writing material and thereby produce sharp lines and characters when applied thereto in simulation of lines and characters produced by ordinary ink on ordinary writing material.

7. In a protective record, the combination with a record material simulating ordinary writing material in appearance and having a degree of capillarity' in excess of that of ordinary writing material and rendering it incapable of receiving legible inscriptions written in other than writing fluid sufficiently non-flowing upon application to the record material as to resist the capillarity thereof to produce lines and characters in simulation of those produced by ordinary in]: on ordinary writing material, of an ink for use therewith including approximately 7% pigment, 62% gum and 30% volatile solvent.

8.. A writing material treated with a mixture of approximately 14% titanium dioxide, 4% glycerol. 45% sodium silicate and 35% water to increase the capillarity thereof over and above that of ordinary writing material, whereby the writing material is rendered incapable of receiving legible inscriptions written in other than writing fluid sufficiently non-flowing upon application to the writing material as to resist the increased capillarity of the treated writing material and thereby produce sharp lines and characters when applied thereto in simulation of those produced by ordinary ink on ordinary writing materlal.

JOHN Q. SHERMAN. WTLBUR A. YACKLEY. 

